This handy applet is a Java implementation of a Windows application written by Kite as a refinement of an old DOS application used by Dart. It allows you to easily track your letter replacements as you work through a cryptogram.

This application requires Sun™ Java™ 1.4.2 for your browser. Look for “Java Software Download” at java.com for an upgrade. This is also called a “Java 2 platform.” Sun is currently shipping Java 1.5.x, so hopefully this application will run on most computers including those not on the “bleeding edge.” Mozilla and IE can tell you about your browser's capability if you put “about:plugins” into the address bar.

When you have the matched each Cypher letter to a Plain Text letter, you can press the [Exchange] button.

The three alphabets show you how the letters swap out. An upper alphabet letter is in the Cypher text and the lower alphabet is always the Plain Text letter that matches the letter above. This is true whether you are working in the top pair, or the lower pair of alphabets.